Expansion-bit



a. P.-. BUTLER. EXPANSION BIT.

APPLICATION F ILED AFR-12,1920.

79 332 Patented May 24, 1921.

UNITED STATES PATENT OFFICE.

GEORGE I. BUTLER, OF NEW HAVEN, CONNECTICUT, ASSIGNOR TO WINCHESTER REPEATING ARMSCQ, OF NEW HAVEN, CONNECTICUT, A CORPORATION.

EXPANSION-BIT.

Specification of LettersPatent Patented May 24., 1921.

- Application filed April 12, 1920. Serial No. 373,047.

T 0 all whom it may concern.

Be it known that I, Gnonon P. BUTLER, a citizen of the United States, residing at New Haven, in the county of New Haven and State of Connecticut, have invented a new and useful Improvement in Expansion- Bits; and I do hereby declare the following, when taken in connection with the accompanying drawings and. the characters of reference marked thereon, to be a full, clear, and exact description of the same, and which said drawings constitute part of this application, and represent, in

Figure 1, a View in side elevation of an expansion bit embodying my invention.

Fig. 2, an edge view thereof with its lower end in longitudinal section to show the looking of the cutter by means of the cutterlocking wedge.

Fig. 3, a detached view in rear elevation of the cutter.

Fig. 4, an end View thereof.

Fig. 5, a detached rear view of the cutterlocking wedge.

Fig. 6, a side view thereof.

Fig. 7, a detached view of the wedge-operating screw.

My invention relates to an improvement in expansion bits, the object being to provide simple, convenient, and reliable means for securing the transversely arranged cutter in any position of close adjustment.

lVith these ends in view, my invention is characterized by the use of a cutter-locking wedge located in a hole in the head of the bit and jammed upon the rear face of the cutter by the head of a screw located in the body at a point above the cutter.

My invention further consists in certain details of construction as will be hereinafter described and pointed out in the claims.

In carrying out my invention, as herein shown, I employ a cutter-locking wedge in the form of a pin 2 having'its lower end cut away to form a beveled gripping-face 3 which is roughened by preference, by vertical serrations, while the upper end of the pin is concaved, as at 4:, to adapt it to fit over the beveled head 5 of a wedge-operating screw 6 located in a transverse screw-hole 7 formed in the enlarged head 8 at the lower end of the bit-shank 9. The said pin 2 is located in an inclined hole 10 leading from the counter-sunk outer end of the screw-hole 7 into the rear wall of the transversely arranged dovetail or under-cut slot 11 formed in the outer face of the head 8 for the reception of the cutter 12, the rear face of which is corrugated or serrated, as

at 13, for co-action with the beveled lower is formed with the usual screw-point 16,

cutting-edge 17, and spur 18.

By loosening the screw 6, the thrust thereof upon the pin 2 is removed so as to permit the cutter 12 to be laterally adjusted in the slot 7, after which the tightening of the screw 6 causes its beveled head 7 to force the beveled face 3 of the wedge 2 into engagement with the serrated face 13 of the cutter, whereby the same is rigidly held against lateral displacement. By preference, the serrations 13 will be exact submultiples of a unit of measure so that they will permit and facilitate the precise setting of the cutter required for holes of given sizes.

I claim:

1. An expansion bit, having a head, a laterally adjustable cutter mounted therein, a forwardly inclined cutter-locking wedge mounted in the head in position to have its lower end engaged with the flat rear face of the cutter, and a wedge-operating screw transversely mounted in the rear face of the head and co-acting with the upper end of the said wedge for forcing the lower end thereof into engagement with the flat rear face of the cutter.

2. An expansion bit, having a head, a laterally adjustable cutter mounted in the lower end thereof, a pin-like wedge mounted in forwardly inclined position within the head and having its lower end beveled for engagement with the flat rear face of the cutter and its upper end concaved, and a screw transversely mounted in the rear face of the head in position for the engagement of its beveled head with the concaved upper end of the pin, whereby the beveled lower end of the same is forced into direct engagement with the flat rear face of the cutter.

3. An expansion bit, having a laterally adjustable cutter, a forwardly inclined cutter-locking wedge engaging with the flat rear face of the cutter, and means engaging with the upper end of the wedge from the back of the bit for forcing the wedge into engagement with the cutter.

4:. An expansion bit, having a head formed in its outer face with a transverse undercut slot, in its inner face with a transverse screw-hole located above the said slot; and with a forwardly inclined hole leading from the vsaid screw'hole into the bottom of the said undercut slot; a cutter located in the under-cut slot; a pin-like wedge located in the saidinclined hole for theengagement of its lower end-with the flat rear face of the cutter; and a screw located in the said transverse screw-hole for engagement with the upper end of the said wedge, whereby the lower end of the same is jammed against the fiat rear face of the cutter.

' In an expansion bit a head; a laterally adjustable cutter mounted in the lower end thereof; a pin-like wedge mounted in an inclined position within the head, having its lower end beveled for engagement with the rear face ofthe said cutter and having its upper end concaved; and a screw mounted in the head in position for the engagement of its beveled head with the concave upper end of the said pin-like wedge for the operation thereof; the said beveled lower end of the wedge and the said rear ing witnesses.

' GEORGE P. BUTLER.

Witnesses I DANIEL H. VEADER, ARTHURP. PAINE. 

